The motor vehicle industry, particularly the passenger car and van portions of the industry, are increasingly relying on flush glass window mounting for improving the appearance of motor vehicles and reducing the aerodynamic drag of the vehicles to make them more fuel efficient. A number of conflicting requirements for such seals makes them difficult and expensive to produce and install. The increasingly complex shape of motor vehicle bodies requires seals that are not simply bent in a plane to surround the top edge of a flat glass window. The seals are formed not only at the radii (corners of the glass) but are also arched vertically to coincide with the curved top surface of the glass and rounded sides of the automobile.
Heretofore, thermosetting materials such as ethylene-propylene-diene-monomer rubber (EPDM) have been used extensively for vehicle window seals. Some complex seals have included portions formed from other materials such as thermoplastic materials, but EPDM has usually been a major portion of the seal. To improve the appearance of motor vehicles, the industry demands window seals that are colored to enhance the appearance of the vehicle, usually by matching the body color. Obtaining a color on EPDM has been less than satisfactory in the past, whereas thermoplastics are readily colored.
Although EPDM is cost effective (inexpensive) as a material, the total cost of making and installing an EPDM seal on a motor vehicle is high. The seal must not only be formed at the radii of the glass by cutting, mitering or welding molded pieces, but it must also be arched in the vertical direction to coincide with the curved glass and rounded sides of the vehicle. To accomplish this with EPDM, a metal support internal to the EPDM is added, usually as the EPDM seal is extruded. Massive and expensive roll forming machinery and tooling and stretch bending equipment and tooling are required to form the extruded seal to the desired configuration in three dimensions. Thus, the total cost, that is the cost of the seal and the capital cost of equipment needed to form it, is high.
It is an object of this invention to provide an improved vehicle door and window channel seal that overcomes the disadvantages of known seals by providing a semi-rigid seal which readily conforms to the desired configuration and allows for a closing action on the window glass. The seal of the invention comprises a channel seal which is a substantially rigid but flexible channel seal and is thermally formed from at least two different polymers, coming together into one profile. The channel seal is preferably used in conjunction with a sealing insert.
More particularly, it is an object of the invention to improve the sealing action against the glass by incorporating an elastic joint of TPE of lower durometer in the base of the channel seal to provide a winking action when a window engages the sealing insert and causes the legs of the window run channel to pivot inwards and compress the sealing insert against the window glass.
Ii is an object of the invention to provide a door and window channel seal in which the channel seal comprises a combination of thermoplastic elastomer (TPE) materials of different durometers which attaches to a vehicle body and can be color matched to an automobile and which can be thermally formed to match the general contour of the vehicle, thus eliminating the need for the expensive, massive, roll forming machinery and tooling and stretch bending equipment and tooling mentioned before.
The channel seal can be thermally formed by extrusion or molding in one piece and conformed to the general contour of the vehicle opening. Thus molded joint lines and the need for cutting, mitering or welding of the carrier member to fit the corners are avoided. The sealing insert can be formed by extrusion of a one-piece, relatively flat resilient rubber member which can be readily provided with a sliding surface, such as a slip coating or flocking.